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Flow diverters represent a useful tool in the treatment of fusiform aneurysms and wide-neck saccular aneurysms which until the advent of this technology were problematic to treat. Pipeline™ Embolization Device (PED) has been described in several series showing high rates of occlusion and being relatively safe. Objective: Shows the experience in four different neurointerventional centres in Barcelona with the PED (Covidien) between February 2010 and October 2013. Methods: We reviewed retrospectively patients treated with PED in four neurointerventional centres in Barcelona between February 2010 and October 2013. Results: Forty-two patients (89.4%) with non-ruptured aneurysms and five (10.6%) post-SAH were treated, with a mean age of 51 years (range 26–76). We treated 67 aneurysms with a mean of 1.4 1–3 PED per patient. We have no mortality and three post-procedural complications with clinical consequences, two of them severe with intracranial haemorrhage and the other with anterior choroidal artery thrombosis. Follow-up was in 45 patients (65 aneurysm) achieving complete occlusion in 90.8% at 12 months of follow-up. Two aneurysms which remained without any changes were distal and fusiform including main bifurcations (3.1%). Conclusion: Treatment by PED of fusiform or wide-neck saccular aneurysms is associated with high rates of occlusion after six and 12 months. Correct selection of the patients, aneurysms and also specific characteristics of the Pipeline device should be known in order to select the best therapeutic option. Our findings suggest that the indication must be judged case by case in the selection of suitable patients for PED therapy. [ABSTRACT FROM AUTHOR]

ABSTRACT We have recently observed an increased risk for vertebral fractures (VF) in a randomized controlled trial comparing the analgesic effect of vertebroplasty (VP) versus conservative treatment in symptomatic VF. The aim of the present study was to evaluate the risk factors related to the development of VF after VP in these patients. We evaluated risk factors including age, gender, bone mineral density, the number, type, and severity of vertebral deformities at baseline, the number of vertebral bodies treated, the presence and location of disk cement leakage, bone remodeling (determining bone turnover markers) and 25 hydroxyvitamin D [25(OH)D] levels at baseline in all patients. Twenty-nine radiologically new VF were observed in 17 of 57 patients undergoing VP, 72% adjacent to the VP. Patients developing VF after VP showed an increased prevalence of 25(OH)D deficiency (<20 ng/mL) and higher P1NP values. The principal factor related to the development of VF after VP in multivariate analysis was 25(OH)D levels < 20 ng/mL (RR, 15.47; 95% CI, 2.99-79.86, p < 0.0001), whereas age >80 years (RR, 3.20; 95% CI, 1.70-6.03, p = 0.0007) and glucocorticoid therapy (RR, 3.64; 95% CI, 1.61-8.26, p = 0.0055) constituted the principal factors in the overall study population. Increased risk of VF after VP was also associated with cement leakage into the inferior disk (RR, 6.14; 95% CI, 1.65-22.78, p = 0.044) and more than one vertebral body treated during VP (RR, 4.19; 95% CI, 1.03-34.3, p = 0.044). In conclusion, nearly 30% of patients with osteoporotic VF treated with VP had a new VF after the procedure. Age, especially >80 years, the presence of inferior disk cement leakage after the procedure, the number of cemented vertebrae, and low 25(OH)D serum levels were related to the development of new VF in these patients, with the latter indicating the need to correct vitamin D deficiency prior to performing VP. [ABSTRACT FROM AUTHOR]

Computational algorithms modeling the insertion of endovascular devices, such as coil or stents, have gained an increasing interest in recent years. This scientific enthusiasm is due to the potential impact that these techniques have to support clinicians by understanding the intravascular hemodynamics and predicting treatment outcomes. In this work, a virtual coiling technique for treating image-based aneurysm models is proposed. A dynamic path planning was used to mimic the structure and distribution of coils inside aneurysm cavities, and to reach high packing densities, which is desirable by clinicians when treating with coils. Several tests were done to evaluate the performance on idealized and image-based aneurysm models. The proposed technique was validated using clinical information of real coiled aneurysms. The virtual coiling technique reproduces the macroscopic behavior of inserted coils and properly captures the densities, shapes and coil distributions inside aneurysm cavities. A practical application was performed by assessing the local hemodynamic after coiling using computational fluid dynamics (CFD). Wall shear stress and intra-aneurysmal velocities were reduced after coiling. Additionally, CFD simulations show that coils decrease the amount of contrast entering the aneurysm and increase its residence time. [ABSTRACT FROM PUBLISHER]

Purpose: The objective of this study is to investigate the feasibility of detecting and quantifying 3D cerebrovascular wall motion from a single 3D rotational x-ray angiography (3DRA) acquisition within a clinically acceptable time and computing from the estimated motion field for the further biomechanical modeling of the cerebrovascular wall. Methods: The whole motion cycle of the cerebral vasculature is modeled using a 4D B-spline transformation, which is estimated from a 4D to 2D+t image registration framework. The registration is performed by optimizing a single similarity metric between the entire 2D+t measured projection sequence and the corresponding forward projections of the deformed volume at their exact time instants. The joint use of two acceleration strategies, together with their implementation on graphics processing units, is also proposed so as to reach computation times close to clinical requirements. For further characterizing vessel wall properties, an approximation of the wall thickness changes is obtained through a strain calculation. Results: Evaluation on in silico and in vitro pulsating phantom aneurysms demonstrated an accurate estimation of wall motion curves. In general, the error was below 10% of the maximum pulsation, even in the situation when substantial inhomogeneous intensity pattern was present. Experiments on in vivo data provided realistic aneurysm and vessel wall motion estimates, whereas in regions where motion was neither visible nor anatomically possible, no motion was detected. The use of the acceleration strategies enabled completing the estimation process for one entire cycle in 5-10 min without degrading the overall performance. The strain map extracted from our motion estimation provided a realistic deformation measure of the vessel wall. Conclusions: The authors' technique has demonstrated that it can provide accurate and robust 4D estimates of cerebrovascular wall motion within a clinically acceptable time, although it has to be applied to a larger patient population prior to possible wide application to routine endovascular procedures. In particular, for the first time, this feasibility study has shown that in vivo cerebrovascular motion can be obtained intraprocedurally from a 3DRA acquisition. Results have also shown the potential of performing strain analysis using this imaging modality, thus making possible for the future modeling of biomechanical properties of the vascular wall. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the suitability of an improved version of an automatic segmentation method based on geodesic active regions (GAR) for segmenting cerebral vasculature with aneurysms from 3D x-ray reconstruction angiography (3DRA) and time of flight magnetic resonance angiography (TOF-MRA) images available in the clinical routine. Methods: Three aspects of the GAR method have been improved: execution time, robustness to variability in imaging protocols, and robustness to variability in image spatial resolutions. The improved GAR was retrospectively evaluated on images from patients containing intracranial aneurysms in the area of the Circle of Willis and imaged with two modalities: 3DRA and TOF-MRA. Images were obtained from two clinical centers, each using different imaging equipment. Evaluation included qualitative and quantitative analyses of the segmentation results on 20 images from 10 patients. The gold standard was built from 660 cross-sections (33 per image) of vessels and aneurysms, manually measured by interventional neuroradiologists. GAR has also been compared to an interactive segmentation method: isointensity surface extraction (ISE). In addition, since patients had been imaged with the two modalities, we performed an intermodality agreement analysis with respect to both the manual measurements and each of the two segmentation methods. Results: Both GAR and ISE differed from the gold standard within acceptable limits compared to the imaging resolution. GAR (ISE) had an average accuracy of 0.20 (0.24) mm for 3DRA and 0.27 (0.30) mm for TOF-MRA, and had a repeatability of 0.05 (0.20) mm. Compared to ISE, GAR had a lower qualitative error in the vessel region and a lower quantitative error in the aneurysm region. The repeatability of GAR was superior to manual measurements and ISE. The intermodality agreement was similar between GAR and the manual measurements. Conclusions: The improved GAR method outperformed ISE qualitatively as well as quantitatively and is suitable for segmenting 3DRA and TOF-MRA images from clinical routine. [ABSTRACT FROM AUTHOR]

This report describes a giant intracavernous carotid aneurysm successfully treated by the placement of a single covered stent. A 40-year-old woman was admitted with a progressive diplopia in relation with palsy of the IV and VI cranial nerves. Magnetic resonance imaging revealed an intracavernous giant aneurysm located at the bifurcation between the origin of a trigeminal artery and the intracavernous portion of the right internal carotid artery. A covered stent was successfully placed, and complete exclusion of the aneurysm was confirmed at 11-month follow-up angiography. The use of covered stents in intracranial vascular structures can now be a feasible way of treating selected cases of wide-necked intracranial aneurysms. [Copyright &y& Elsevier]